There have been many advances in the design of sleeping bags. One improvement has been to use overlapping batts of insulating material between the outer shell and the inner liner. These batts are positioned to extend laterally from one side of the longitudinally placed access zipper to the other side of the longitudinally placed access zipper. One lateral edge of each of the batts is secured to the outer shell and the other lateral edge is secured to the inner liner. It is these lateral seams which are seen on many modern sleeping bags to give the sleeping bag a quilted look. Even though the stitching does not go all the way through the bag, it does create needle holes in the shell and the liner.